Apparatus for controlling combustion



H/flfA/TOR fiWMDM 3 Sheets-Sheet 1 July 24, 1923.

F. H. BROWN APPARATUS FOR CONTROLLING COMBUSTION Original Filed March28, 1917 July 24, 1923. 1,463,142

F. H. BROWN APPARATUS FOR CONTROLLING COMBUSTION Original Filed March 281917 3 Sheets- Sheet 5 WA *1 Mt Patented July 24, 1923.

UNITED STATES PATENT OFFICE.

FRANCIS H. BROWN, 0F GLENOLDEN, PENNSYLVANIA, ASSIGNOR, BY MESNE ASSIGN-MENTS, TO THE HAGAN CORPORATIUN, OF PITTSBURGH, PENNSYLVANIA, A

CORPORATION OF PENNSYLVANIA.

APPARATUS FOR CONTRDLLING COMBUSTIGN.

Original application filed March 28, 1917, Serial No. 157,821. Dividedand this application filed October so, 1920. Serial No. 420,619.

T 0 all whom it may concern.

Be it known that I, FRANCIS H. BROWN, residing at Glenolden, in thecounty of Philadelphia and State of Pennsylvania, a citizen ofthe UnitedStates, have invented or discovered certain new and useful Improvementsin Apparatus for Controlling Combustion, of which improvements thefollowing is a specification.

The invention described in this application is a division of anapplication Serial Number 157921, filed by me March 28, 1917, consistingof a combination of mechanisms for controlling combustion, a prominentfeature of which is the automatic control of the fuel feed by means ofmechanism regulated by and in accordance with variations of pressure inthe furnace posterior to the bed of fuel.

The invention is designed to be utilized in conjunction with any desiredtype of fur nace and in conjunction with any desired type of fuel, asfor example, solid, liquid, or gaseous fuel, so that the introduction ofsuch fuel to the point of combustion will be accurately controlled inaccordance with the varying conditions which are taking place in thefurnace.

A further purpose of this invention is to utilize in conjunction withthe automatic control of the fuel feed, mechanism as for example astolrer or its equivalent means for automatically varying the furnacepressure in accordance with the variation in load on the furnace. Thisload varies in character in accordance with the character of the furnaceemployed and in a boiler furnace the load would be the variation in thedemand for steam while in a heating furnace it might be the variation inheat within the furnace.

For the purpose of illustrating my invention I have shown in theaccompanying drawings typical embodiments of it which are at presentpreferred by me since these embodiments will give in practicesatisfactory and reliable results although it is to be understoodthatthe various instrumentalities of which the. invention consists andby means of which my method can be carried out, can be variouslyarranged and organized and that my invention is not limited to a precisearrangement and organization of these instrumentalities as herein shownand descrlbed.

- Fig. 1 represents in sectional elevation one type of a furnace havingcombined therewith my improvements in controlling mechanisms; Fig. 2represents in side elevation on an enlarged scale an automatic regulatmgdevice seen in Fig. 1; Fig. 3 shows in sectional elevation thecontrolling valve seen in Fig. 4.; Fig. 4 shows partly in section andpartly in elevation the pressure regulator seen in Fig. 1; Fig. 5 showsin side elevation another embodiment of my invention illustrating adifferent type of fuel feeding mechanism for feeding liquidor gaseousfuel; 6 shows a section on line VIVI, Fig. 2; and Fig. 7 is a viewsimilar to Fig. 1 illustrating another embodiment of my invention.

It is to be understood in carrying out my novel method in practice thatI do not desire to be limited to any special type of stoker or fuelfeeding mechanism, to any special type of regulator controlled by thevariation in load on the furnace, to any special type of a regulatorcontrolled by varying conditions posterior to the point of combustion,such as for example, a pressure regulator, or to the steps of utilizingnatural or mechanical draft or any special type of mechanism forcontrolling forced draft.

1 designates a furnace of any desired or conventional type, and isillustrated in the drawings, it is indicative of one of the individualfurnaces of a battery of boilers for the generation of steam so that theload on each furnace is the variation in steam demand. 2 designates theash pit and 3 the fuel feeding mechanism which is intended to disclosethe equivalent of a stoker, and consists of a travelling grate, themovement of which is controlled by an engine 4 of any desired orconventional type and which is illustrated diagrammatically in Figure 1.It will be understood that the engine 4 is operatively connected withthe travelling grate 3 in order to impart movement thereto.

5 designates a combustion chamber which is in communication with theindividual stack 6, through which the products of combustion pass tothemain furnace stack 7. 8 designates a boiler, in which the steam isficient clearness to enable one to comprehend the operation thereof.

11 designates a conduit which is in communication with the combustionchamber 5 and has its free end extending above the liquid in a container1 and into the chamber 13 of an inverted tank 14. This tank 1 1 islocated within the outer inverted tank 13 and these tanks have theirlower ends sealed by the liquid in the container 12. The inverted tanks141 and 15 are carried at one end of a lever 16 fulcru ed in any desiredmanner and provided with an adjustable counterbalance 17.

18 designates a link which is connected witha valve 19 which controlsadmission and discharge of motive fluid through the pipes 20 and .21 toopposi. e ends of a motor chamber-22, and in which is located arec1procatory piston 23. 24 designates a piston red the lower end ofwhich connected provided with an inlet 31 and an outlet 32.

The inlet communicates by means of a port 33 with the interior of thevalve casing 30 and the port 29 registers at times with the port 33. Thevalve 28 is shown as a cup-shaped valve having the ports 34 through oneend to balance the pressure of motive fluid against the valve. The inlet31 communicates by means of a valve-con trolled conduit with the steamdome 9.

The outlet 32 communicates by .neans of a valve controlled conduit 36with the engine 4. The piston rod 2 1 of the pressure regulator 10'hasconnected to its upper end a cable 37 which passes over pulleys 3S andis connected to a damper 39 in the auxiliary draft conduit 10 whichcommunicates with the ash-pit 2. The damper 39 is provided with anadjustable counterbalance 11. The auxiliary draft conduit 10communicates with the main draft conduit 12 which is in communicationwith each furnace of the battery. The furnace may be operated undereither a natural or forced draft and T have illustrated in Figure 1 adraft conduit 13 for the natural draft so that when the damper 141 isclosed, the furnaces will operate under natural draft. When the damper1a is open, as indicated in dotted lines in Figure 1, the blower a5 isin communication with the maindraft conduit 42 so that the furnaces willoperate under forced draft. ihe blower 4-5 is intended to illustrate theconventional type of forced draft wherein the blower is actuated by anengine 16 which is provided with a governor 17, so that the speed of theengine can be automatically controlled.

Each individual stack 6 is provided with a damper 18 having acounterbalance 49 and provided with a cable 50 which extends into aposition accessible to the engineer in order to provide for the manualcontrol of the oamper 18. Each individual stack 6 is pro vided with anautomatically controlled damper 51 which is provided with a pulley 52around which passes a cable 53, which is provided with a counterbalance5 1, said counterbalance being adjustable. The cable 53 is connected toa piston rod 55 of a motor 56. The admission and exhaust of motive fluidto the motor 56 is controlled by means of a pilot valve 57 and the stemof the valve, as indicated by 58, is connected to a lever 59 to whichpivoted an adjustable connection (30, the other end of which isconnected with a lever 61. The lever 61 is provided with an adjustablecounterweight 62 and an adjustable counterbalance The lcver is actuatedby a diaphragm vmotor (3st of any conventional type, one side of whichis subjected to variations in steam pressure which is introduced intoproximity to said diaphragm through a steam conduit 65 which is incommunication with the steam dome 9. The lever 59 is connected by meansof a link 66 with an elbow lever 67 which is fulcrumed to a fixed point.This elbow lever 67 carries at one end shoe 63 which is slidably mountedupon a guide 69 pivoted at its lower end to a fixed point as 70 on abracket 71 which is adjustably fixed to the piston rod 55 which isconnected to the cable 53. The upper end of the bracket 71 is providedwith a worm72 adapted to be manually adjusted and which meshes with arack 73 at the upper end of the guide 69 in order to provide for theangular adjustment of said guide 69. This bracket '71 and its adjunctsform a compensating mechanism, so that a graduated adjustment of thedamper 51 is automatically provided in accordance with variations in thesteam pressure.

It will be seen from Figure 6 that the shoe 58 is pivotally carried bythe bifurcated end of the lever 67.

In Figure 1, I have illustrated the mechanism for providing an automaticcontrol of the fuel feeding mechanism which can be employed in case asolid fuel is used, and

in Figure 5. I have illustrated a typical mechanism which can beemployed in case a liquid or gaseous fuel is used. The cable 37 inFigure 5 would be connected to the pressure regulator 10 and controlsthe auxiliary draft conduit 40 to the individual furnace in the samemanner as already described with reference to Figure 1, and I havetherefore indentified thecorresponding parts by the same'referencecharacters. Connectedto the cable 37 is a cable 74 which passes around acontrolling valve 75 and is provided with acounterbalance 76. The valve75 automatically controls the passage of fuel of a liquid or gaseousnature through the nozzle or injector 77. The other parts of themechanism for controlling combustion would correspond to thetypical'mechanism illustrated in Fig. 1.

The operation of my novel apparatus will now be readily apparent tothose skilled in the art to which this invention appertains and is asfollows motor 56 to cause the damper 51 to move in the direction ofopening and thereby increase the pressure posterior to the point ofcombustion, such as for example, the furnace pressure in the combustionchamber, since such combustion chamber is now in communication with theatmosphere through the stack 6 of the individual furnace. This change inpressure causes the lever 16 to be actuated to operate the pilot valve19 and admit motive fluid to the motor 22 and thereby actuate the pistonrod 24:. The piston rod 24 will move downwardly thereby causing thelever 25 to move thevalve stem 27 upwardly, and steam is permitted topass from the conduit 35 through the inlet 31, the ports 33 and 29,through the port 32 into the conduit 36 and thence to the engine 4 tocause the fuel to be fed into thefurnace. This downward movement of thepiston rod 24 actuates the cable 37 to open the valve 39 and permit thedraft for combustion to pass from the maindraft conduit 42 into theash-pit 2 of the individual boiler.

In order to illustrate one manner of carrying out my method, I havepreferred to show a single instrumentality for simultaneouslycontrolling the operation of the fuel feeding mechanism and theintroductionof draft for combustion, but it is to be understood that itis within the scope of my invention to employ separate mechanisms forsuch control in accordance with conditions and requirements met with inpractice.

When the load on the furnace decreases, such as for example, a decreasein the demand for steam, the motor 56 will be actuated to cause thedamper 51 to close to a degree corresponding to the change in steampressure, and the fuel feeding mechanism and the primary draft will becorrespondingly actuated to decrease the'amount of fuel being fed andthe amount of air introduced for combustion. Owing to the provision ofthe compensating mechanism which is best illustrated in Figures 2 and 6,the damper 51 is not moved to a fully open or closed position on thevariation in steam pressure but a graduated movement is provided.Thebracket 71, carried by thGPlS- ton rod 55 as it moves in onedirection or the other, actuates the shoe 68 to move the valve stem 58and correspondingly control. thepilot valve 57. It is not-essential inall cases arising in practice to use all of the steps of my method asherein set forth and they can be used alone and independently of eachother or in any combination.

In so far as I am aware, I am the first in the art to devise the step ofautomatically controlling the fuel feed by Variations in furnaceconditions posterior to the point of combustion, such as for example,the variations in the furnace pressure. I am also the first 1n the art,in so far as I am aware, to

employ in conjunction with such tep, the

automatic control of the primary draft in accordance with varyingconditions posterior to the point of combustion, either alone or inconjunction with the step of automatically varying conditions posteriorto the point of combustion in accordance with variations in load on thefurnace or furnaces. It is therefore to be understood that my claims tosuch features are to be interpreted with the scope to which a genericinvention is entitled. i

In some cases arising in practice, the damper 51 and its adjuncts may bedis pensed with and the damper 48 can be manually controlled to vary theconditions of pressure posterior to the point of combustion.

Another embodiment of my invention is seen in Figure 7, wherein insteadof controlling the damper 51 by variations in steam pressure, it iscontrolled by variations in furnace conditions posterior to the point ofcombustion, such as for example, the furnace pressure. In thisembodiment, the steam regulator seen in Figure 2 is dispensed with, andthe cable 37 is connected to or forms a part of the cable 53 whichcontrols the stack damper and also actuate the controlling means forcontrolling the introduction of fuel- It is to be understood that inconjunction with this embodiment seen in F ure 7, I dispense with thedamper 39 and its automatic control, and the engine is automaticallycontrolled by steam passing from the dome 9 through the conduits 78, thebypass 79and the steam regulating valve 80, the valve 81 being closedand the valves 82 opened and the governor being disconnected. in themethod first described in connection with Figure 1 the valve 82 would beclosed and the valve 81 would be open. In accordance with my presentinvention, one is enabled to maintain a constant rate of combustion ineach furnace, irrespective of the thickness of the bed of fuel or theresistance olfered to the draft.

It will be apparent that I have devised a new and useful method ofcontrolling combustion, v-shich embodies the features of vantageenumerated as desirable in the state ment of the invenuionandthe abovedescrip tion, and while I have, in the present instance, shown anddescribed typical embodiments thereof which will give in practicesatisfactory and reliable results, it is to be understood that theseembodiments are susceptible of modification in various particularsWithout departing from the spirit or scope of the invention orsacrificing any of its advantages.

it is characteristic of the invention herein described that the pressureof gases in the furnace is automatically variable by and in accordancewith the static pressure of steam or vapor in the boiler and that therate of operation of the motor for the fuel feeding mechanism isvariable by and in accordance with changes of pressure of the gases asde termined by the static pressure of vapor in the boiler.

l. claim herein as my invention:

1, in an apparatus for controlling combustion, the combination of afurnace, means for feeding fuel into the furnace and means forregulating the feed of fuel by and in accordance with variations infurnace pres sure.

2. In an apparatus for controlling combustion, the combination of afurnace, means for fe ling fuel to the furnace, means for supplying airfor combustion and means for regulating the feed of fuel and the supplyof air by and in accordance with variations furnace pressure.

3. In an apparatus for controlling combustion, the combination of afurnace, means for feeding fuel. to the furnace, means for supplying airfor combustion to the furnace and means operative by and in accordancewith variations in furnace pressure for simultaneously controlling thefeed of fuel and the supply of air.

4. In an apparatus for controlling combustion, the combination of afurnace, means for regulating the pressure of gases in the furnace,means for feeding fuel to the furnace and means operative by and inaccord ance with the pressure of the furnace for controlling the feed offuel.

5 In an apparatus for controlling combustion, the combination of afurnace, means for regulating pressure of'gases in the furnace, meansfor feeding fuel to the furnace, means for feeding air for combustion tothe furnace and means for controlling the feed of fuel and the supply ofair by and in accordance with variations in furnace PIGC'QUFG.

(3. .n r apparatus for controlling com bustion the combination of aboiler having 7 O furnace, means for varying the pressure of the gasesin the furnace by and in accordance with changes in the static pressureof vapor generated, means for feeding fuel to the furnace and means forvarying the rate o feel of fuel by and in accordance with vaimaons infurnace pressure.

In an apparatus for controlling cou bust-ion, the combination of aboiler having a furnace, means operative by and in accord auce withclizuiges of pressure of vapor generated for controlling the dischargeof gases from the furnace, means for feeding fuel-to the furnace, meansfor supplying air for comluistion to the fur race and means operative byand in secure tnce with changes of pres sure in the furnace forregulating the feed of fuel and the supply of air.

8. In a furnace structure, the eombinatio'i of furnace chamber,mechanism for feeding fuel automatically, mechanism includins; a movableelement subjected in opposite directions to furnace pressure and toatmospheric pressure for changing the rate of operation of the fuelfeeding-mechanism.

9. In a furnace structure the combination of the furnace chamber, amechanical fuel feeding mechanism and a speed changing device applied tosaid fuel feed, of an automatic control of said speed changing deviceincluding a movable element subjected in opposite directions to furnacechamber pres sure and to atmospheric pressure.

10. In a furnace structure the combination with a furnace chamber, amechanical fuel feed, and a speed changing device applied to said fuelfeed, of an automatic con changing device including a movable elementmaintained in equilibrium between atmospheric pressure and the sum oftwo forces; one, furnace-chamber pressure, and the other, a forceconstant while said draft passageways remain constant, substantially asdescribed.

12. In a furnace structure the combination with a furnace chamber, amechanical fuel feed, and a speed changing device ap plied to said fuelfeed, of an automatic control for said speed changin device including amovable element maintained in equilibrium between atmospheric pressureand the sum of two forces: one, furnace-chamber pressure, and the othergravity, substantially as described.

13. In a furnace structure the combination with a furnace chamber and amechanical fuel feed, of a counter-weighted fluidsealed bellcommunicating with said furnace chamber, a speed changing device"applied to said fuel feed, and means operated by said bell forcontrolling said speed-changing device, substantially as described.

14. In a furnace structure the combination with a furnace chamber and ame chanical fuel feed, of a liquid-sealed bell, an adjustablecounterweight for said bell, pneumatic connection from said furnacechamber to said bell, a speed-changing de vice applied to said fuelfeed, and means operated by said bell for controlling said 15. In anapparatus for controlling combustion, the combination of a boiler havinga furnace, a damper regulating the discharge of gases from the furnace,means controlled by the pressure of steam for operating the damper,means for feeding fuel to the furnace and means operative by and inaccordance with the pressure in the furnace for controlling the feed offuel.

16. In an apparatus for controlling combustion the combination of aboiler having a furnace, a damper for regulating the flow of gases fromthe furnace, means for feed ing fuel to the furnace, means for feedingair for combustion to the furnace, means operative by and in accordancewith changes of pressure of steam for regulating the stack damper, andmeans for controlling the feed of fuel and the supply of air by and inaccordance with variations in furnace pressure.

17. In an apparatus for controlling combustion, the combination of aboiler having a furnace, a stack damper for controlling the flow ofgases from the furnace, means operative by and in accordance with thestatic pressure of vapor generated for controlling the stack damper, astoker for feeding fuel to the furnace and means regulating theoperation of the stoker by and in accordance with furnace pressure.

In testimony whereof, I have hereunto set my hand.

FRANCIS H. BROWN.

